Capillary pressure

From ArticleWorld

Capillary pressure refers to the deviation in pressure across the interface between two immiscible fluids. The difference in pressure varies proportionately with the surface tension and is inversely proportional to the effective radius of the interface. It also depends upon the wetting angle of the liquid that is on the surface of the capillary.

The 'wetting' characteristics of liquids

A liquid has a tendency to wet the surface of a solid if the molecules of the liquid have a stronger attraction to the molecules of the solid. The wetting characteristics of a liquid can be quantified by measuring the angle of contact of a drop of liquid that is placed on the surface of an object. The wetting characteristics of a liquid also determine the fact whether it can penetrate a void in a solid and fill it.